I remember when playing a couple of months ago, there was a barrier block. Is this accessed by a command? If so, what is it? Thanks in advance

1 minute ago, jacks_username. said:

I remember when playing a couple of months ago, there was a barrier block. Is this accessed by a command? If so, what is it? Thanks in advance

That is most likely a custom block. Getting this block can be achieved quite easily though, you can simply create one by doing:
/lb copy 1 (/os lb for your own map)
/lb edit 767 blockdraw 4 (This Will make the block invisible)
/lb edit 767 name Barrier (Changes the name of the block)
/lb edit 767 blockslight no (removes the shadow from underneath the block)
if you want to use it in your global blocks you would do /gb instead
Also, I am 99% sure there isnt a barrier in the normal blocks